Humidity control apparatus employing lever means to actuate a push button switch



29, 1954 R. P. FLAGG HUMIDITY CONTROL APPARATUS EMPLOYING LEVER MEANS To ACTUATE A PUSH BUTTON SWITCH Filed April 50, 1962 INVENTOR. RAWOIVD P PLAG'G W/dflM ATTOEME) United States Patent Ofiiice 3,lfi3,72i@ Patented Dec. 29, 1954 HUMIDITY CONTROL APPARATUS EMPLOYINQ LEVER MEANS TG ACTUATE A PUSH BUTTQN SWlTCI-l Raymond P. Flagg, Minneapolis, Minru, assignor to Honeywell line, a corporation of Delaware Filed Apr. 30, 1962, Ser. No. 191,082 4 Claims. (Cl. 2tlil---6LG l) The present invention is concerned with an improved humidity control device; in particular, the device comprises a four section element which changes in length upon a change in the moisture content of the surrounding air to vary the position of an integral switch actuating lever depending upon a control point which is established by selecting the position of one end of the element.

With the advent of humidity changing apparatus in the form of humidification and dehumidification equipment, the need for control devices which respond to the humidity level in the surrounding air to regulate the operation of the humidity changing apparatuses has greatly increased. While the applicant recognizes that the use of such control devices to control both humidity and dehumidifying equipment is old, the increased acceptance of such apparatus has greatly increased the volume and the number of suppliers now available for such control devices. Obviously, the increase in demand increases the Competition, which results in the need for improvements to maintain or better the performance of such apparatus and yet decrease the cost.

The applicant has provided a humidity control which has a continuous moisture responsive element extending between a plurality of rollers to provide a plurality of parallel segments which provide a combined output to change the distance between a fixed lever and a movable switch actuating lever. The device has an integral switch which is operated depending upon the eiiect of the moisture level of the air surrounding the element. The position of the fixed ends of the element are determined by a control point adjusting device. The adjusting device comprises a cam attached to a shaft which protrudes from eithe' the top or the side of a case depending upon the particular type of installation in which the humidity contrcl device is to be used.

An object of the present invention is to provide an improved humidity control device having a continuous length of moisture responsive element which extends between a single roller on a switch actuatin lever and a pair of rollers on a control point adjusting lever to form four parallel active lengths of element.

Another object of the present invention is to provide a humidity control device with a control point adjusting means operating on a lever at one of two points depenting upon whether a control point adjusting shaft is desire to project from the upper side or the back side of a case.

Another object of the present invention is to provide a humidity control device having an integral switch and a sviitch operating lever with an element extending between the switch operating lever and a second lever provided with a strain release means so that upon the adjustment or a second lever a control point of the device is changed. I

These and other objects of the present invention will become apparent upon the study of the following specification and claims of which: 7

FIGURE 1 is a front cutaway view of the humidity control device showing the integral. switch and the multisegment element for operating the switch.

FiGURE 2 is a side cutaway'view oi the device as shown in FL'GURE 1 looking toward the left of the device.

FIGURE 3 a top View of the device as shown in no lo FIGURE 1 with a dotted showing of the control point adjusting cam.

FIGURE 4 is a second embodiment of the control device shown in FIGURE 1 wherein the control point adjusting shaft extends from the back side.

Referring to FIGURE 1, an enclosure or casing 18 has a back side or base 11 to which the components of the unit are attached. Mounted in the lower portion of easing Ill is an integral snap-acting switch 12. The switch housing 13 has a bottom portion 14 to which two terminals 15 and 20 are connected to form the connection points for the electrical circuit of a de-humidi ication or humidification apparatus which can be connected to be operated by switch 12. The switch has a solid L-shaped bracket 21 which is attached by an upper leg to terminal 15 at the inner side of switch base 14. Member 21 is held away from base 14 by a screw 22 and against the force of a spring 23 compressed between a shorter leg of member 2 1 and switch cover 13. The function of spring 23 is to maintain member 21 rigid in a position as selected by screw 22.. A switch contact blade 24 is also attached to terminal 15. The blade has an open portion to circumvent the shorter leg of member 21. A contact 25 is attached at the lower end 3-4- of blade 24. Contact 25 engages a fixed contact which is attached to the switch base 14 and is adjusted by a threaded portion 31 to change the operation of the switch. A bias spring 32 provides an over-center operation of switch operating member 24 by placing a force between the lower end of member 24 and member 21. The point of engagement of the bias spring 32 on member 21 provides the over-center snap acting pivot when a switch operating button 33 moves member 24. When operating button 33 is pushed inward, member 24 moves at a lower end to the left. When a sullicient movement is obtained to move the member past an over-center position, contact 25 will snap against the fixed contact to close the switch and the circuit between terminals and 2% Upon the release of operating button 33, a reverse operation of the switch will take place. By the adjustment of screw 22 and the position of contact Stl, the switch can be set to have a certain operating diiierential which establishes the amount of movement of member 33 to obtain a switch operation cycle.

A switch operating lever is pivoted about a shaft 41 which is attached in a perpendicular manner to base 11. Lever id has a switch operating portion #22 which engages button 33 and a free end 43 for holding a curved support member or a rod 44 parallel to shaft 41 to support one end of a moisture responsive element 2-5.

Contained in the upper portion of enclosure it) is a control point selecting lever Si and an element support lever 51', which are both pivotaliy mounted on a shaf'tSI Z which is attached perpendicular to base 11 and parallel to shaft 41. Lever 51 has a first portion 53 which is attached to a bias spring 54 connected between portion 53 and a connecting tab 5&3 attached to base 11 to bias lever 51 in a counterclockwise direction. Lever 51 has a free end as on which a Whittle tree type or balancing equalizing member s1 is supported. Member 61 supports a pair of curved support members or rods 62 and cs which are mounted to be parallel to support 4- 7 Element is of a conventional type which is made of some material such as nylon ribbon to change in length as the moisture in the surrounding air changes. The element is made in a continuous ribbon to be strung between rods 62., 63 and 44. The element extends over each of the rods 62 and 63 and doubles over rod 44 to provide four substantially parallel sections of element 4-5 which operate together to provide the desired .aovement of the switch operating level By means of the whiffie 3 tree member 61 and the rods, the tension on the separate strands of the element 45 is maintained equal.

Lever St) has two tabs 76 and 71 as shown in FIGURE 2. With a cam '73 attached to a shaft 74 as shown in FIGURE 1, cam 73 adjusts the positions of tab 70 and thus lever 50 depending upon the desired control point eeded. Upon rotating shaft 74, cam 73 rotates to vary the position of lever 54 The calibration of the device is adjusted by screw '75 to establish the position maintained between levers 5t and 51; however, upon a decrease in the distance between free end 60 and free end 43 by the shortening of the element 45, lever 51 can move away from lever 59 to provide the strain release operation.

A second embodiment, as shown in FIGURE 4, makes use of a cam which is attached to a shaft 81 similar to the cam 73 and shaft 74- associated with FIGURE 1. Shaft 81 is mounted to the back or base 11 of the case so that upon rotation of shaft 31, the position of tab 71 is changed to adjust lever 5%. With this particular embodiment, the same type of operation of the unit is attained with shaft 81 projecting from the rear of the unit for adjusting the control point. The selection of the particular embodiments such as that of FIGURE 1 or that of FIGURE 4 would depend upon what type of mounting the device may have and the position desired for the control point adjusting shaft '74 or 81.

Operation As shown in FIGURE 1, switch 12 is open. Upon a decrease in the moisture content of element 45, the switch operating lever is moved counterclockwise to close the switch by moving contact 25 against contact 3%. Once the switch is against the contact and button 33 has moved as far to the left as possible, no further movement of lever 40 can exist in a counterclockwise direction. A further decrease in the length of element would result in a strain on the element unless some sort of strain release was provided. Spring 54 urges lever 51 against lever 5%) in a counterclockwise direction. The difference in the position of the levers is selected by screw '75 which provides the control point adjustment for factory calibration. When element 45 contracts beyond the limit of movement of member 40, lever 51 pivots in a clockwise direction to release the possible tension which could exist on element 45. Spring 54' is strong enough to maintain the element tension within the operating range of the switch 12, but the spring is capable of releasing lever 51 for strain release purposes.

Upon the rotation of shaft 74- to move cam 73, lever is moved about shaft 52 to position lever 5 In this manner, the control point of the device is selected. By the contour of cam '73, the rotation of the shaft in a farthermost counterclocl twise direction as shown in FIG- URE 3' lifts tab 7% of FIGURE 2 on a hump 85 of the cam to relax the element and p'rovidefor a positive off operation of switch 1-2; Upon the rotation of shaft 74in a clockwise direction as shown inFIGURE 3, tab 7% of FIGURE 1 falls into a notch 9 on cam 73 to reposition lever 51 in a farthermost counterclockwise position to maintain a positive on operation of switch 12.

Referring to FIGURE 4, the adiusting earn 80 is associated with tab 71 on lever 50. The same type of operation is provided as previously mentioned for the device of FIGURE 1 and FIGURE 3 when shaft 81 is rotated as cam ht) has the same contour as the cam '73 as shown in FIGURE 3. In one extreme position, tab is moved to maintain the unit in a positive oti operation position, and movement of shaft 81' in the opposite extreme position provides for the positive on operation.

While the invention is described in one particular manner, the intention of the applicant is to limit the invention to the scope of the appended claims.

I claim: i

1. In a humidity control device, a base, a switch having a push button operator, and mounted on said base, a

first bell crank lever pivotally mounted at a lower end of said base, said lever having a first extremity for engaging said push button operator when said crank is moved in a first direction and a second extremity extending parallel to said lever end or" the base, a second bell crank lever pivotally mounted at an upper end of said base, said second lever having a first extremity extended in spaced relationship with said second extremity of said first lever, a whiflle-tree like member having two curved support members, said member being supported by said first extremity of said second lever, a third curved support member mounted on said second extremity of said first lever, a continuous ribbon humidity responsive element which changes in length as the moisture level of the surrounding air changes, said element being supported by said curved members whereby four effective lengths of element extend between said spaced levers, a cam, a shaft mounted in an upper end of said base, means connecting said cam to said shaft, a third bell crank lever pivotally supported on said base, said third lever having an extremity engaging said second lever, said cam engaging an extremity of said third lever to select a position depending upon the rotation of said shaft to a predetermined position, said position establishing a humidity level at which said switch of the device is operated, a strain release spring connected between said second lever and said base, said spring maintaining tension on said element and allowing movement of said second lever independently of said third lever upon said humidity responsive element shortening in total length beyond a predetermined amount.

2. In a humidity control device, a case, a switch having a push button operator and mounted in said case, a first bell crank lever pivotally mounted at a lower end of said case, said lever having a first extremity for engaging said operator when said crank is moved counterclockwise and a second extremity, a second bell crank lever pivotally mounted to move in a plane parallel to the movement of said first lever at an upper end of said case, said second l'ever having a first extremity extended in spaced relationship with said second extremity of said first lever and a second extremity, a balancing member having two element supporting means, said member being" supported by said first extremity of said second lever, a third element supporting means on said second extremity of said first lever, a continuous ribbon humidity responsive element which changes in length as the moisture levelv of the surrounding air changes, said element being supported by said element supporting means whereby said element is held between said element supporting means by having a double thickness wrapped over said third supporting means so four lengths of element extend between said spaced levers, a earn, a shaft mounted in said case, means connecting said cam to said shaft, a third bell crank lever pivotally supported on said base, said third lever having an extremity engaging said first extremity of said second lever, said cam engaging said third lever to select a position depending upon the rotation of said shaft, said position establishing a humdity level causing operation of said switch, and strain release means connected between said base and said second extremity of said second lever, said strain release means providing for movement of said second lever independently of said third lever upon said humidity responsive element shortening beyond a predetermined amount.

3. In a moisture responsive control device, a case, a switch mounted in said case, a switch operating lever pivotally mounted at one end of said case, said lever being adapted to operate said switch and having a free end, a first and a second lever pivotally mounted on a shaft attached in an opposite end of said case, means for ad justing the relative positions of said first and second levers with respect to each other, said first lever having a free end, a moisture responsive element which changes in length with humidity level of the surrounding air, means for extending a plurality of lengths of said element between said free end of said switch operatingdever and said free end of said first lever whereby a change in humidity of the surrounding air changes the distance between said mentioned free ends, bias means for biasing said first lever in one direction to maintain a predetermined tension of said element whereby upon said element contracting to increase the tension of said element above said predetermined tension said first lever is pivoted to act as a strain release, and a control point adjusting means mounted in said case, said adjusting means engaging said second lever to vary the position of said free end of said first lever.

4. In a moisture responsive control device, a case, a switch mounted in said case and having an operating button, a switch operating lever pivotally mounted at one end of said case, said lever engaging said button and having a free end, a first and a second lever pivotally mounted on a shaft attached in an opposite end of said case, means for adjusting the relative positions of said first and second levers with respect to each other, said first lever having a free end, said second lever having at least two projecting tabs, one of said tabs extending in said opposite end of said case and a second of said tabs extend to a back portion of said case, a moisture responsive element which changes in length with humidity level of the surrounding air, said element being a continuous ribbon means for extending a plurality of lengths of said element between said free end of said switch operating lever and said free end of said first lever whereby a change in humidity of the surrounding air changes the distance between said mentioned free ends, bias means for biasing said first lever in one direction to maintain a predetermined tension of said element whereby upon said element contracting to increase the tension of said element above said predetermined tension said first lever is pivoted to act as a strain release, and a control point adjusting means comprising a cam mounted in said case, said adjusting means engaging one of said tabs said second lever to vary the position of said free end of said first lever, said cam having a low and a high area at its extremes to tighten or relax said element for positive on or positive oif operation of said switch.

References Cited by the Examiner UNITED STATES PATENTS 1,237,470 8/17 Carrier 200-61.06 1,995,430 3/35 Lewis 200-61.06 2,198,131 4/49 Shaw ZOO-61.06 2,262,342 11/41 Shaw ZOO-61.06 2,780,687 2/57 Keenan 20061.06 2,887,544 5/59 Gustavsson 200-6L06 2,949,514 8/60 Barthel 200-6 1.06

BERNARD A. GILHEANY, Primary Examiner.

ROBERT K. SCHAEFER, Examiner. 

1. IN A HUMIDITY CONTROL DEVICE, A BASE, A SWITCH HAVING A PUSH BUTTON OPERATOR AND MOUNTED ON SAID BASE, A FIRST BELL CRANK LEVER PIVOTALLY MOUNTED AT A LOWER END OF SAID BASE, SAID LEVER HAVING A FIRST EXTREMITY FOR ENGAGING SAID PUSH BUTTON OPERATOR WHEN SAID CRANK IS MOVED IN A FIRST DIRECTION AND A SECOND EXTREMITY EXTENDING PARALLEL TO SAID LEVER END OF THE BASE, A SECOND BELL CRANK LEVER PIVOTALLY MOUNTED AT AN UPPER END OF SAID BASE, SAID SECOND LEVER HAVING A FIRST EXTREMITY EXTENDED IN SPACED RELATIONSHIP WITH SAID SECOND EXTREMITY OF SAID FIRST LEVER, A WHIFFLE-TREE LIKE MEMBER HAVING TWO CURVED SUPPORT MEMBERS, SAID MEMBER BEING SUPPORTED BY SAID FIRST EXTREMITY OF SAID SECOND LEVER, A THIRD CURVED SUPPORT MEMBER MOUNTED ON SAID SECOND EXTREMITY OF SAID FIRST LEVER, A CONTINUOUS RIBBON HUMIDITY RESPONSIVE ELEMENT WHICH CHANGES IN LENGTH AS THE MOISTURE LEVEL OF THE SURROUNDING AIR CHANGES, SAID ELEMENT BEING SUPPORTED BY SAID CURVED MEMBERS WHEREBY FOUR EFFECTIVE LENGTHS OF ELEMENT EXTEND BETWEEN SAID SPACED LEVERS, A CAM, A SHAFT MOUNTED 